Fabrication of Sulfur Defect Rich ZnIn<sub>2</sub>S<sub>4</sub>/SnSe<sub>2</sub> Photocatalyst with Ohmic Junction for Efficient Water to Hydrogen Energy Conversion
Xianghu Wang, Xuehua Wang, Tianyu Shi, Alan Meng, Lei Wang, Shaoxiang Li, Guicun Li, Xiaohu Yu, Zhenjiang Li
Abstract
The development of a noble‐metal‐free cocatalyst is of great significance for boosting photocatalytic H 2 evolution performance. Herein, SnSe 2 is developed as a cocatalyst to in situ attachment on the surface of sulfur defect rich ZnIn 2 S 4 (Vs‐ZIS) via a simple hydrothermal method. Owing to the intimate atomic‐level interface and the different work function between Vs‐ZIS and SnSe 2 , a particular Ohmic junction with internal electric field is formed in Vs‐ZIS/SnSe 2 , which facilitates the electrons in Vs‐ZIS transfer to SnSe 2 and participate in H 2 evolution reaction rapidly. Moreover, the abundant S vacancies also benefit the separation of photocarriers in Vs‐ZIS/SnSe 2 . The optimized Vs‐ZIS/SnSe 2 photocatalyst performs a high H 2 evolution rate of 29.34 mmol h −1 g −1 under visible light ( λ > 420 nm) and an apparent quantum efficiency of 12.25% at 420 nm. Herein, constructive model on developing effective cocatalyst is afforded, and expediting photocarriers transfer through interfacial modulating.